Abstract: A head-mounted display may include a display system and an optical system in a housing. The display system may have displays that produce images. Positioners may be used to move the displays relative to the eye positions of a user's eyes. An adjustable optical system may include tunable lenses such as tunable cylindrical liquid crystal lenses. The displays may be viewed through the lenses when the user's eyes are at the eye positions. A sensor may be incorporated into the head-mounted display to measure refractive errors in the user's eyes. The sensor may include waveguides and volume holograms, and a camera for gathering light that has reflected from the retinas of the user's eyes. Viewing comfort may be enhanced by adjusting display positions relative to the eye positions and/or by adjusting lens settings based on the content being presented on the display and/or measured refractive errors.

Abstract: The disclosure discloses a driving device for door opening and closing, which includes: a box body; a permanent magnet synchronous motor arranged inside the box body, an output shaft of the permanent magnet synchronous motor extending along a vertical direction; and a gear set arranged inside the box body and connected with the output shaft of the permanent magnet synchronous motor, and a gear at a tail end of the gear set is provided with a connecting rotating shaft that extends along a vertical direction and is used for connecting a door panel. The above driving device for door opening and closing uses the permanent magnet synchronous motor as a driving source, which is matched with the gear set to implement transmission, the door panel is driven to rotate by the connecting rotating shaft on the gear at the tail end of the gear set.

Abstract: Disclosed are a door lock and a door system, the door lock includes: a lock body, the lock body including a lock case, a spring bolt assembly and a shifting sleeve, the spring bolt assembly being slidably arranged in the lock case, so as to be able to extend and retract relative to the lock case, the shifting sleeve being rotatably arranged in the lock case, and the shifting sleeve being in transmission connection with the spring bolt assembly; and a first handle assembly, the first handle assembly being provided with a locking head and a motor, the locking head being rotatabversly provided with a shifting head, the shifting head being in transmission connection with the shifting sleeve, and an output shaft of the motor being in transmission connection with the shifting head, so as to be able to drive the shifting head to rotate.

Abstract: An apparatus for drilling annulus ring hole, comprising: a down-the-hole (DTH) percussion hammer assembly, the DTH percussion hammer assembly comprising one or more DTH percussion hammers, an annulus ring structural housing having an outer diameter (OD) and an inner diameter (ID) for accommodating the DTH percussion hammers within space between the OD and the ID of the annulus ring structural housing; one or more drill pipes being connected serially with each other forming a string of drill pipes, the string of serially connected drill pipes being connected to the DTH percussion hammer assembly; a top pipe with one or more exhaust openings being connected to the string of serially connected drill pipes; an air or fluid distributor being connected to the top pipe; and a rotary head providing rotational turning motion for the apparatus, and the rotary head being connected to the air distributor.

Abstract: An apparatus for drilling hole, comprising: a cluster drill of down-the-hole (DTH) percussion hammers having two or more DTH percussion hammers; and a special distributor having rotatable swivels for sourcing compressed air or pressurized fluid from independent supply sources and distributing to the DTH percussion hammers; wherein the DTH percussion hammers are arranged such that one or more circumferential layers of drill bits are formed covering the drilling area; and wherein within each circumferential layer, at least one DTH percussion hammer is supplied with the compressed air or pressurized fluid from an independent supply source that is different from the independent supply source supplying the other DTH percussion hammers.

Abstract: A system, application platform, and method that helps a recipient receiving a phone call identify a caller in advance of answering the incoming call. According to the invention, a caller is able to create a multimedia content using a software application platform present in the mobile device, upload the created multimedia content in a cloud storage space, thereafter, when the caller places a call to any recipient, the multimedia content automatically streams from the cloud storage space into the recipient's mobile device in a display loop until the recipient responds to the incoming call and during the subsequent conversation helping the recipient identify the caller.

Abstract: An apparatus for drilling annulus ring hole, comprising: a down-the-hole (DTH) percussion hammer assembly, the DTH percussion hammer assembly comprising one or more DTH percussion hammers, an annulus ring structural housing having an outer diameter (OD) and an inner diameter (ID) for accommodating the DTH percussion hammers within space between the OD and the ID of the annulus ring structural housing; one or more drill pipes being connected serially with each other forming a string of drill pipes, the string of serially connected drill pipes being connected to the DTH percussion hammer assembly; a top pipe with one or more exhaust openings being connected to the string of serially connected drill pipes; an air or fluid distributor being connected to the top pipe; and a rotary head providing rotational turning motion for the apparatus, and the rotary head being connected to the air distributor.

Abstract: A printed circuit board includes a group of pads suitable to be soldered to a respective group of solder-balls of a device. Each pad of the group has a crack initiation point on its perimeter at a location where cracks in a solder-ball are anticipated to start after that solder-ball is soldered to that pad. For a pad of that group having a microvia located therein, a center of that microvia is located farther than a center of that pad from its crack initiation point. For a pad of that group having a trace merging along a portion of its perimeter, that portion does not include a vicinity of that crack initiation point.

Abstract: A printed circuit board includes a group of pads suitable to be soldered to a respective group of solder-balls of a device. Each pad of the group has a crack initiation point on its perimeter at a location where cracks in a solder-ball are anticipated to start after that solder-ball is soldered to that pad. For a pad of that group having a microvia located therein, a center of that microvia is located farther than a center of that pad from its crack initiation point. For a pad of that group having a trace merging along a portion of its perimeter, that portion does not include a vicinity of that crack initiation point.

Abstract: A method and apparatus for using a single computer program code base to provide a program that is operable in either a client-server mode or a standalone mode are provided. In one embodiment, a client logic element has one or more proxy objects, each of which implement an interface that is neutral with respect to the client-server mode and the standalone mode. A server logic element has one or more service objects. Each of the service objects implements the interface. The interface implementations are not bound to any code that is specific to the client-server version or the standalone version. In the stand-alone version, the client side logic invokes the server side logic directly through the interfaces, as implemented by the service objects. In the client-server version, the client side logic invokes the server side logic through the same set of Java interfaces.